# db2_lob_read

(PECL ibm_db2 >= 1.6.0)

db2_lob_read — Gets a user defined size of LOB files with each invocation

### Beschreibung

db2_lob_read(resource `$stmt`, int `$colnum`, int `$length`): string|false

Use db2_lob_read() to iterate through a specified column of a result set and retrieve a user defined size of LOB data.

### Parameter-Liste

`stmt`
  A valid `stmt` resource containing LOB data.
`colnum`
  A valid column number in the result set of the `stmt` resource.
`length`
  The size of the LOB data to be retrieved from the `stmt` resource.

### Rückgabewerte

Returns the amount of data the user specifies. Returns `false` if the data cannot be retrieved.

### Beispiele

Beispiel #1 Iterating through different types of data

`<?php
/* Database Connection Parameters */
$db = 'SAMPLE';
$username = 'db2inst1';
$password = 'ibmdb2';
/* Obtain Connection Resource */
$conn = db2_connect($db,$username,$password);
if ($conn) {
$drop = 'DROP TABLE clob_stream';
$result = @db2_exec( $conn, $drop );
$create = 'CREATE TABLE clob_stream (id INTEGER, my_clob CLOB)';
$result = db2_exec( $conn, $create );
$variable = "";
$stmt = db2_prepare($conn, "INSERT INTO clob_stream (id,my_clob) VALUES (1, ?)");
$variable = "THIS IS A CLOB TEST. THIS IS A CLOB TEST.";
db2_bind_param($stmt, 1, "variable", DB2_PARAM_IN);
db2_execute($stmt);
$sql = "SELECT id,my_clob FROM clob_stream";
$result = db2_prepare($conn, $sql);
db2_execute($result);
db2_fetch_row($result);
$i = 0;
/* Read LOB data */
while ($data = db2_lob_read($result, 2, 6)) {
echo "Loop $i: $data\n";
$i = $i + 1;
}
$drop = 'DROP TABLE blob_stream';
$result = @db2_exec( $conn, $drop );
$create = 'CREATE TABLE blob_stream (id INTEGER, my_blob CLOB)';
$result = db2_exec( $conn, $create );
$variable = "";
$stmt = db2_prepare($conn, "INSERT INTO blob_stream (id,my_blob) VALUES (1, ?)");
$variable = "THIS IS A BLOB TEST. THIS IS A BLOB TEST.";
db2_bind_param($stmt, 1, "variable", DB2_PARAM_IN);
db2_execute($stmt);
$sql = "SELECT id,my_blob FROM blob_stream";
$result = db2_prepare($conn, $sql);
db2_execute($result);
db2_fetch_row($result);
$i = 0;
/* Read LOB data */
while ($data = db2_lob_read($result, 2, 6)) {
echo "Loop $i: $data\n";
$i = $i + 1;
}
} else {
echo 'no connection: ' . db2_conn_errormsg();
}
?>`

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

    Loop 0: THIS I
    Loop 1: S A CL
    Loop 2: OB TES
    Loop 3: T. THI
    Loop 4: S IS A
    Loop 5:  CLOB
    Loop 6: TEST.
    Loop 0: THIS I
    Loop 1: S A BL
    Loop 2: OB TES
    Loop 3: T. THI
    Loop 4: S IS A
    Loop 5:  BLOB
    Loop 6: TEST.

### Siehe auch

- db2_bind_param() - Binds a PHP variable to an SQL statement parameter
- db2_exec() - Executes an SQL statement directly
- db2_execute() - Executes a prepared SQL statement
- db2_fetch_row() - Sets the result set pointer to the next row or requested row
- db2_prepare() - Prepares an SQL statement to be executed
- db2_result() - Returns a single column from a row in the result set

`↑` and `↓` to navigate • `Enter` to select • `Esc` to close • `/` to open